[class^=col-] > div{
    border: 1px solid red;
    /* padding-top: 10px; */
    padding-bottom: 10px;
    margin-bottom: 10px;
}
img{
    width: 100%;
}
@media screen and (max-width:768px){
    [class^=col-] > div{
        width: 320px;
        margin: 0 auto;
        margin-bottom: 10px;
    }
}